Automatic rod line adjuster



Dec. 8, T936. w. s. GEARY AUTOMATIC R OD LINE ADJUSTER Filed May 22, 1936 2 Sheets-Sheet l v R 3 w m+ w R R ATTORNEYS.

8, 1936. w, s GEARY I 2,063,802

AUTOMATIC ROD LINE ADJUSTER Filed May 22, 1956 2 Sheets-Sheet 2 INVENTOR.

Will-i. am Er E E ail-H M I ATTORNEY Patented Dec. 8, 1936 UNITED STATES PATENT OFFICE 11 Claims.

This invention relates to improvements in automatic rod line adjusters.

In oil well pumping systems wherein a single power plant is utilized to operate a plurality of distant wells by means of reciprocating rod lines,

tion of the power plant is discontinued in the afternoon while the temperature is relatively high, the lines will become too short when the temperature decreases, as during the night, and as a result the pumping jacks will sometimes be broken or pulled away from their foundations.

It is, therefore, an important object of the present invention to provide an improved rod line adjuster which will automatically compensate for longitudinal expansion or contraction of a reciprocating rod line while the line is in use.

Another object of the invention is to provide a rod line adjusting mechanism which will automatically compensate for longitudinal contraction in a rod line while the line is idle.

A further object is to provide an improved fluid-regulated reciprocating rod line adjuster including a fluid pump actuated by the reciprocating movement of the line.

Other objects and advantages of the invention will appear in the following detailed description, taken in connection with the accompanying drawings, forming a part of this specification, and in which drawings:-

Figure l is a view in side elevation of the improved automatic rod line adjuster associated with a portion of the rod line.

Figure 2 is a View partly in end elevation and partly in cross section taken on the line 22 of Figure 1.

Figure 3 is a vertical sectional View of a fluid pump preferably associated with the rod line adjuster.

Figure 4 is a horizontal sectional view of a fluid control valve preferably associated with the rod line adjuster.

Figure 5 is an enlarged vertical sectional view of a cylinder sealing cap preferably forming a part of the rod line adjuster.

In the drawings, where for the purpose of illustration is shown only a preferred embodiment of the invention and wherein similar reference characters denote corresponding parts throughout the several views, the letter A may generally designate the improved automatic rod line adjuster, comprising a pair of swinging posts B, a cylinder C pivotally supported on the posts, a piston D longitudinaly slidable in the cylinder, a fluid reservoir E, a fluid pump F associated with the reservoir, pump actuating means G, a control valve H, control valve regulating means I, a relief valve J and relief valve regulating means K.

Referring first to the swinging posts B, they are preferably square in cross section and may each be made by welding together two pieces and. II of chanel iron. One end of each post may be pivotally secured to a suitable foundation 12 as by bearings I3.

Pivotally secured to the opposite end of each post as by bearings I4 is an elongate cylinder C. This cylinder may comprise an outer tube l5 which may be made from steel casing material of a length depending upon the length of the rod line with which it is to be associated and an inner concentric tubular brass liner l6. An internally threaded cast steel cap I! provided with an eye I8 may be screwed to one end IQ of the cylinder whereby that end is adapted to be connected to a pumping jack (not shown) or other load by means of a short length of rod line 20. The other end 2| of the cylinder may be sealed by an internallythreaded cast steel cap 22 shown in Figure 5. A diametrical passageway in the cap 22 forms an inlet 23 and an outlet 24 to the cylinder and. more particularly to the interior of the liner I6. An axial shaft-receiving passageway 25 having associated therewith a' suitable packing gland 26 may also be provided in the cap 22. Secured to one side of the cylinder in circumferentially contacting relation is a channel bar 21 providing a vertical fastening surface 28. Co-acting with the lower portion of the channel bar 21 to form aligning horizontal fastening surfaces 29 beneath the cylinder is an angle bar 30 secured in circumferentially contacting relation to the lower half of the opposite side of the cylinder. The swinging post bearings 14 preferably are positioned subjacent the surfaces 23 and secured to the bars 21 and 30 as by bolts 3|.

Referring now to the piston D, it is arranged to longitudinally slide in the cylinder, and more particularly in the liner I6 thereof and preferably forms a fluid tight joint with the liner. The piston may include a cylindrical head 32 provided with a shaft 33 adapted to extend through the axial passageway 25 of the cylinder end cap 22. At its exteriorly projecting end the shaft may be provided with an eye 34 whereby the piston is adapted to be connected to a rod line 35 extending to the power plant (not shown).

As to the fluid reservoir E, a cylindrical barrel 36 supported in an upright position on a suitable foundation 3'! may be employed. Fluid pump F may be secured to the channel bar 21 adjacent the surface 28 thereof as by clamps 38. As shown in Figure 3, the pump may comprise a central body portion 39, a base40 having an inlet, an air chamber 4| having an outlet, a pair of valves bar 2? associated with the cylinder.

42, one clamped between the portion 39 and the base 40, and the other between the portion 39 and the chamber ii, a barrel 43 communicating with the central body portion between the valves 42, and a reciprocable plunger rod 44 having one end 45 positioned in the barrel and carrying a pair or cups 46, the other end 41 of the plunger rod extending from the barrel and terminating in a threaded portion 138. The pump inlet may be connected to the fluid reservoir as by a flexible pipe 49 while the pump outlet may be connected to the cylinder inlet 23 as by a passageway 50 preferably provided with a one-way or check valve 5! adapted to prevent a return flow along the passageway 5fl-from the cylinder.

In order to continuously actuate the pump F by utilizing the reciprocating movement of the rod line, the following pump actuating means G may be employed. A bell crank lever 52 having one arm 53 pivotally and adjustably secured to the threaded end of the plunger rod 44 as by nuts 54 threaded thereon may be pivoted to a suitable bracket 55 attached to the channel The other arm 55 of the lever 52 may be connected by a pivoted link 5'! to the outer end of a bracket 58 attached to and projecting laterally of one of the swinging posts B.

A control valve H may be provided for regulating the flow of fluid from the pump 15 to the cylinder C. As shown in Figure 4, the control valve may comprise a cylindrical main body portion 59 having a cylindrical axial bore 6!) communicating with a pair of spaced apart annular chambers forming an inlet port BI and an outlet port 62. A piston rod (33 having a pair of spaced apart piston heads 64 and 85 adapted to slidingly contact the axial bore 65 is provided. I When the piston rod is positioned as shown in Figure 4, the inlet and outlet ports 6! and 62 are positioned between the piston heads 64 and 65 thereby permitting a fluid flow through the valve. The piston rod may be shifted so that the piston head 64 is positioned between the inlet and outlet ports 6i and 62 thereby preventing a fluid flow through the valve. The ends of the cylindrical body portion 59 are of course sealed as by removable disc- 7 like plates 66 and 61. A spring 68 may be interposed between the plate 65 and one end 69 of the piston rod. The other end 10 of the rod may extend through and outwardly project from a suitably packed central opening in the plate 61 and may be provided with a pair of oppositely disposed notchesll. The control valve I-I may be secured to the channel bar 2! as by a suitable bracket 12. Communication between the fluid pump and the control valve inlet port 6| may be provided as by a pipe 13 extending from that portion of the passageway 50 between the pump and the check valve 5| to the inlet port. Communication between the control valve outlet port 62 and the fluid reservoir may be provided by means of a flexible pipe 14.

Referring now to the control valve regulating means I, it may comprise a bell crank lever 15 pivotally secured to the control valve bracket 12. One arm 15 of the lever 15 is preferably forked whereby a pivotal connection is obtained with the piston rod 53 at the notches H therein. The other arm ll of the bell crank lever is associated with a laterally projecting bracket 18 secured to one of the swinging posts B by means of a rod 79 pivoted at its upper end 80 to the arm 11. The threaded lower end 8i of the rod 19 may loosely extend through an aperture in the bracket 18. Nuts 82 and 83 may be adjustably secured on the end 8| of the rod in spaced relation one above and one below the bracket.' The spring 68 in the control valve preferably is of a strength to counterbalance the shifting effect exerted upon the piston rod 63 by the weight of the lever arm 71, rod 19 and nuts 82 and 83 whereby the valve will remain in either a closed or an open position.

Relief valve J may be provided for the cylinder outlet 24 and as shown in Figure 5 it may comprise a tubular valve body 84 having one end 85 secured in the cylinder outlet, the opposite end 86 being provided with a suitable giand 81. The valve proper may include a valve head 88 adapted to seat against the end 85 of the valve body 84, a

valve stem' 89 extending through and projecting from the gland 8'8, and a spring 90 urging the valve stem outwardly whereby to releasably hold the valve in a closed position. A lateral outlet opening 9| in the valve body may be connected to the fluid reservoir E by means of a flexible pipe 92.

Referring to the relief valve regulating means K, it may include a lever 93 of the first class pivotally secured to a bracket 94 secured to the channel bar 21. One end 95 of the lever may be positioned beneath the relief valve stem and the other end 96 may be pivotally secured to the upper end 91 of a rod 98. The threaded lower end 99 of this rod 98 is adapted to loosely extend through an opening in the end I of a bracket llll rigidly secured to, and laterally projecting from one of the swinging posts B. A nut I02 may be adjustaby secured to the threaded lower end 99 of the rod 98 in spaced relation below the bracket IOI.

In operation, the improved automatic rod line adjuster may be positioned near the well, with the rod line 35 from the pumping power attached to the piston rod, a connection from the pumping jack such as the relatively short length of rod line 20 being attached to the cylinder, the swinging posts being substantially vertical and the remaining parts being positioned as shown in Figure 1 when the well pump is halfway through its stroke, it being understood that the reservoir E and the cylinder C have been supplied with a quantity of fluid. When the pumping power relieves the tension on the rod line, the cylinder will be pulled toward the well through the action of the pumping jack thereby tilting the swinging posts B toward the well. The bracket 58 will thereupon swing downwardly, exerting a pull on rod 51 which through the bell crank lever 52 will cause the fluid pump plunger 44 to draw a quantity of fluid through the flexible pipe 49 from the fluid reservoir and thence through the lower valve 42 into the pump F. When the pumping power exerts a pull upon the rod line the cylinder will be pulled toward the power and the swinging posts will tilt in the opposite direction thereby exerting an upward push through bracket 58 and rod which through the bell crank lever 52 will cause the pump plunger to force the fluid through the upper valve 42 of the pump F into the passageway 50. Control valve H being in an open position, the fluid will pass through the pipe 13 and will return to the reservoir through the flexible pipe 14. the direction of flow being shown by the full line arrows in Figure 1. Normally the control valve regulating means I and the relief valve regulating means K will not be afiected by the swinging of the posts B.

When an increase in temperature causes elongation of the rod line 35, the swinging posts 13 will tilt a greater degree toward the well resulting in contact of the bracket 18 and nut;82 of the control valve regulating means I whereby the rod 19 will be moved upwardly and will cause the bell crank lever 15 to shift the control valve piston rod 63 to a closed position. The return of fluid to the reservoir E being prevented when the valve H is closed, the fluid will be forced by the pump F along the passageway 50 andinto the cylinder thereby moving the piston 32 whereby to compensate for the elongation of the rod line 35 whereupon the swinging posts B will return to a normal position. The bracket 18 will thereupon contact the nut 83 and will exert a downward pull on the rod 18 whereby to open the control valve H. Thereupon the fluid will cease flowing to the cylinder because of a lesser resistance to the flow of fluid through the control valve and back of the fluid reservoir. 7

When a decrease in temperature causes longitudinal contraction in the rod line 35, whether or not the line is in use, the swinging posts B will abnormally tilt toward the power plant until the bracket lfll associated with the relief valve regulating means K contacts the nut I02 whereby to exert a downward pull upon the rod 98. The lever 93 will thereupon press the valve stem 89 and cause the relief valve to open in spite of the resistance of the spring 90. If the rod line is not in use, the relief valve will be continuously held open, whereas if the line is in use and reciprocating, the valve will open and close as the posts swing back and forth. In either case, fluid will escape from the cylinder and return to the fluid reservoir through the flexible pipe 92, thereby permitting the piston to move in the cylinder in a direction toward the power whereby to compensate for the contraction in the rod line. The bracket IOI will thereupon move out of contact with the nut I02 and permit the relief valve to close under the influence of the spring 90 whereby further escape of fluid from the cylinder will be prevented.

Thus it will be seen that an improved fluid operated and controlled rod line adjuster has been provided which will automatically compensate for elongation in a reciprocating rod line and which will automatically compensate for contraction of the line whether or not the rod line is in use.

Various changes may be made in the form of invention herein shown and described, without departing from the spirit of the invention or the scope of the following claims.

I claim:

1. Automatic length-adjusting mechanism for a rod line comprising an elongate cylinder adapted tobe connected to a load, a longitudinally slidable piston. in the cylinder adapted to be connected to the rod line, means automatically operable upon a length variation in the rod line for introducing fluid into the cylinder to move the piston in a direction to compensate for the rod line length variation, and means to cause discontinuance of the introduction of fluid into the cylinder upon movement of the piston relative to the cylinder a distance substantially equal to the rod line length variation.

2. Automatic length-adjusting mechanism for a reciprocating rod line comprising an elongate cylinder adapted to be connected to a load, a longitudinally slidable piston in the cylinder adapted to be connected to the reciprocating rod line, a pump, means associated witl. the rod line for actuating the pump, a fluid passageway between the pump and the cylinder, fluid control means cooperating with the passageway and adapted upon a length variation in the rod line to cause introduction of fluid into the cylinder to move the piston in a direction to compensate for the rod line length variation and upon movement of the piston relative to the cylinder a distance substantially equal to the rod line length variation to cause discontinuance of the introduction of fluid into the cylinder.

3. Automatic length-adjusting mechanism for a reciprocating motion transmitting line comprising an elongate cylinder adapted to be connected to a load, a longitudinally slidable piston in the cylinder adapted to be connected to the reciprocating line, a fluid pump, means associated with the reciprocating line for continuously actuating the pump, a fluid passageway from the pump to the cylinder, a valve associated with the passageway and normally positioned to divert fluid therefrom, and control means for the valve and operable upon variation in the length of the reciprocating line to change the position of said valve in order tocause fluid to pass into the cylinder whereby to move the piston in a direction to compensate for the line length variation, said control means being adapted to return the valve to its normal position upon substantial compensation of the line length variation.

4. Automatic length-adjusting mechanism for a reciprocating motion transmitting line comprising a swinging post, an elongate cylinder pivotally secured to the post and adapted to be connected to a load, a longitudinally slidable piston in the cylinder adapted to be connected to the reciprocating line, a fluid pump, means associated with the reciprocating line for continuously actuating the pump, a fluid passageway from the pump to the cylinder, a valve associated with the passageway and adapted to normally divert fluid therefrom, and control means for the valve associated with the swinging post, said control means being operable upon abnormal swinging movement of the post due to a variation in the length of the reciprocating line tochange the position of said valve in order to cause fluid to pass along said fluid passageway into the cylinder whereby to move the piston in a direction to compensate for the line length variation, said control means being adapted to return the valve -to its normal position upon substantial compensation of the line length variation.

. 5. Automatic length-adjusting mechanism for a reciprocating motion transmitting line comprising a swinging post, an elogate cylinder pivotally secured to the post and adapted to be connected to a load, a longitudinally slidable piston in the cylinder adapted to be connected to the reciprocating line, a fluid pump including a reciprocable plunger, pump actuating means associated with the swinging post for transmitting reciprocating movement from the line to the pump plunger, a fluid passageway from the pump to the cylinder, a relief valve for the cylinder, and control means for the relief valve associated with the swinging post, said control means being operable upon abnormal swinging movement of the post to open the valve.

6. Automatic rod line length-adjusting mechanism comprising an elongate cylinder adapted to be connected to a load, a longitudinally slidable piston in the cylinder adapted to be connected to the line, a normally closed relief valve for the cylinder, and control means for the relief valve operable upon variation in the length of the line to open the valve.

'7. Automatic length-adjusting mechanism for a reciprocating motion transmitting line comprising a swinging post, an elongate cylinder pivotally secured to the post and adapted to be connected to a load, a longitudinally slidable piston in the cylinder adapted to be connected tothe reciprocating line, a normally closed relief valve for the cylinder, and control means for the relief valve associated with the swinging post, said control means being operable upon abnormal swinging movement of the post due to a variation in the length of the line to open the valve.

8. Automatic length-adjusting mechanism for a reciprocating motion transmitting line comprising an elongate cylinder adapted to be connected to a load, a longitudinally slidable piston in the cylinder adapted to be connected to the reciprocating line, a fluid pump, means associated with the reciprocating line for continuously actuating the pump, a fluid passageway from the pump to the cylinder, a control valve associated with the passageway and normally positioned to divert fluid therefrom, control valve, operating means for changing the position of the control valve to cause fluid to pass through the passageway into the cylinder upon longitudinal expansion of the line whereby to move the piston in a direction to compensate for said longitudinal expansion, said control valve operating means being adapted to return the control valve to its normal position upon substantial compensation for said expansion of the line, a normally closed relief valve for the cylinder, and relief valve operating means for opening the relief valve to permit fluid to escape from the cylinder upon longitudinal contraction of the line whereby to enable movement of the piston in a direction to compensate for said longitudinal contraction, said relief valve operating means being adapted to return the relief valve to its normal position upon substantial compensation for the contraction of the line.

9. Automatic length-adjusting mechanism for a reciprocating motion transmitting line comprising an elongate cylinder adapted to be connected to a load, a longitudinally slidable piston in the cylinder adapted to be connected to the reciprocating line, a fluid pump continuously actuated by the reciprocating line, a fluid passageway from the pump to the cylinder, a check valve in said passageway adapted to prevent a return flow from the cylinder, a control valve associated with the passageway and normally positioned to divert fluid therefrom, control valve operating means for changing the position of the control valve to cause fluid to pass through the passageway into the cylinder upon longitudinal expansion of the line whereby to move the piston in a direction to compensate for said longitudinal expansion, said control valve operating means being adapted to return the control valve to its normal position upon substantial compensation for said expansion of the line, a normally closed relief valve for the cylinder, and relief valve operating means for opening the relief valve to permit fluid to escape from the cylinder upon longitudinal contraction of the line whereby to enable movement of the piston in a direction to compensate for said longitudinal contraction, said relief valve operating means being adapted to return the relief valve to its normal position upon substantial compensation for the contraction of the line.

10. Length-adjusting mechanism for a reciprocating rod line comprising swinging supporting means, an elongate cylinder pivotally secured to the supporting means and adapted to be connected to a load, a longitudinally slidable piston in the cylinder adapted to be connected to the reciprocating line, a fluid pump including a reciprocable plunger, pump actuating means associated with the swinging supporting means for transmitting reciprocating movement to the pump plunger, a fluid passageway from the pump to the cylinder a check valve in the fluid passageway adapted to prevent a return flow from the cylinder, a control valve associated with the passageway and normally positioned to divert fluid therefrom, control valve operating means associated with the swinging supporting means for changing the position of the control valve to cause fluid to pass through the passageway into the cylinder upon longitudinal expansion of the line whereby to move the piston in a direction to compensate for said expansion, said control valve operating means being adapted to return the control valve to its normal position upon substantial compensation for said. expansion, a normally closed relief valve for the cylinder, and relief valve operating means associated with the swinging supporting means for opening the relief valve to permit fluid to escape from the cylinder upon longitudinal contraction of the line whereby to enable movement of the piston in a direction to compensate for said contraction, said relief valve operating means being adapted to return the relief valve to its normal position upon substantial compensation for said contraction of the line.

11. Length-adjusting mechanism for a reciprocating rod line comprising swinging supporting means, an elongate cylinder pivotally secured to the supporting means and adapted to be connected to a load, a longitudinally slidable piston in the cylinder adapted to be connected to the reciprocating line, a fluid reservoir, a pump adapted to pump fluid from the reservoir and including a reciprocable plunger, pump actuating means associated with the swinging supporting means for transmitting reciprocating movement to the pump plunger, a fluid passageway from the pump to the cylinder, a check valve in the fluid passageway adapted to prevent a return flow from the cylinder, a control valve associated with the pas sageway and adapted to normally divert fluid therefrom and return it to the reservoir, control valve operating means associated with the swinging supporting means for changing the position of the control valve to cause fluid to pass through the passageway into the cylinder upon longitudinal expansion of the line whereby to move the piston in a direction to compensate for said expansion, said control valve operating means being adapted to return the control valve to its normal position upon substantial compensation for said expansion, an outlet passageway from the cylinder to the reservoir, a normally closed relief valve associated with the outlet passageway, and relief valve operating means associated with the swinging supporting means for opening the relief valve to permit fluid to escape from the cylinder upon longitudinal contraction of the line whereby to enable movement of the piston in a direction to compensate for said contraction, said relief valve operating means being adapted to return the relief valve to its normal position upon substantial compensation for said contraction of the line.

WILLIAM S. GEARY. 

